Unassisted exercises for the abdomen, back and torso have proven less than satisfactory. One of the main difficulties is that unassisted exercises often must be performed in postures that are less than optimal for desired isolation and effect. For example, unassisted sit-ups and "crunches" provide good exercise for the abdominal muscles, but they are difficult to perform in good form and impose unnecessary strain on the neck, shoulders and lower back. To reduce strain on the neck, a person typically puts his hands behind his neck for support, and this posture, in turn, undesirably curls the shoulders inwardly.
A variety of machines have been developed to assist in abdominal exercises. In one known machine, the user is seated in an upright position and curls and uncurls his body against an adjustable resistance. Such machines are relatively expensive and bulky.
More recently an exercise device known as an abdominal roller ("ab roller") has enjoyed great popularity. The device provides a neck support rigidly connected between a pair of curved rocker arms. While the ab roller assists isolating the abdominal muscles, because of the rigid support, the motion of the neck is determined solely by the curved arms of the machine, not by the anatomy of the user. Since users differ considerably, the machine-constrained motion is inappropriate for many. Moreover the ab roller occupies a considerable volume, is bulky for transport, and exercises only one muscle group. Accordingly, there is a need for a more compact and versatile device for assisting exercise.
It is another object of the invention to provide support to the head and neck and the extremities (arms and legs) in other applications such as physical therapy or therapeutic massage.